DE34010C - Process for the preparation of acid or neutral calcium phosphate from phosphorites or bones by treating them with highly carbonated water under pressure - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

CLASS 16: Fertilizer preparation. -7

MICHEL CAHEN in BRUSSELS.

Patented in the German Reich on September 2, 1884.

It is known that carbonic acid is the Lime carbonate · and tribasic phosphoric acid lime dissolves, but so far one has this theoretical reaction has not yet been put to practical use in industry. . In which ordinary atmospheric pressure, carbonic acid is only slightly soluble in water and hence their solution is only a very weak acid, which dissolves only a few calcium salts able; but with increasing air pressure the solubility of carbonic acid increases and consequently their solution in the water will also attack the calcium salts all the more strongly dissolve. Therefore, this property can be used to dissolve phosphorites, by a strong solution of carbonic acid under pressure the lime carbonates as well as the tri-basic phosphoric acid lime dissolves and the other constituents and gaits, especially . the silica, leaves behind. If defatted bones are used, they are released the phosphoric acid lime and the bone cartilage remains completely unaffected, which latter is particularly suitable in this state for glue production.

After the solution of lime salts obtained in this way is still under high Pressure has been poured off or filtered, it is brought back under normal pressure. the superfluous carbon dioxide escapes and is caught again in order to produce another Operation to be used. The lime carbonates fall again and the solution contains only acidic phosphoric acid lime, which is used to represent superphosphates or phosphoric acid can be used. However, it will during the escape the carbonic acid, the solution is warmed to 1 oo °, In addition to the carbonate of lime, neutral phosphoric acid lime and the mixture of the Both can be used directly as fertilizer, adding this salt especially to the fine divided states is also assimilated by the plants.

The purpose of this method is to use an inexpensive dissolving agent, since the larger one Part of the carbonic acid is taken again and again; when exercising the same, the Bone cartilage is not attacked when treating bones and it allows processing poor silica-rich phosphorites. An apparatus used to carry out this process is described in the following:

A is the gas container for the carbon dioxide.

-B B ' are tubes through which the carbon dioxide is removed from the gas container by both suction and pressure pumps CC .

DD ¹ represent small water pumps which, with each piston stroke, press the amount of water to CC which is necessary to dissolve the carbonic acid at the applied pressure.

The carbonated solution is passed through the tubes EE ' to the circular tubes FFFF, which distribute the solution into the vats 1, 2, 3,' 4. These vats are used to open up the phosphorites or bones. In the designated in Fig. 1

Claims (2)

In position, the carbonated solution penetrates through the open valve G into the vessel H, and this contains the most leached masses. The solution absorbs calcium salts and goes out of No. ι through the valve / according to No. 2 or H ', then through the open valve J according to No. 3, in which the latter are the fresh phosphorites or bones which saturate the carbonated solution with calcium salts. The saturated solution passes through the valve Af2 and through a second circular tube N and a connecting tube O into the receiving vessel P. . The residues are from No. 4 removed. The jar no. 4 is then filled with fresh material, so it becomes No. 1, while No. 3 is emptied, and so on. The containers PP ', which are used alternately, let the excess carbonic acid through the valves Q. and Q.' escape into the gasometer. 2 and 3 show the leaching tubs in vertical section and side view (but on a smaller scale). They can be reproduced as required and, under certain circumstances, a single one can suffice, in which case the whole system is very simplified. The phosphorites or bones are poured into this apparatus through the manhole at the top, as required; the exhausted masses are emptied through the lower hole T '. The solution of carbonic acid produced under high pressure comes through E into the vessel, penetrates the layers from bottom to top and, impregnated with the calcium salts, goes from the top through pipe O, Patenτ claims: 1. The preparation of acid phosphoric acid lime by opening up the phosphorites or bones by means of carbonic acid, which is dissolved in water under high pressure, thereby adding carbonate of lime the acidic phosphoric acid lime goes into solution while releasing the pressure Calcium carbonate precipitates and phosphoric acid lime remains in solution. 2. The preparation of neutral phosphoric acid lime by the same process with the modification that, when the pressure is released, the solution is heated to 10 ° C whereby the acidic phosphoric acid lime is transformed into neutral, which falls with the carbonate of lime. For this purpose ι sheet of drawings